What is the electron configuration for bromine?

Long hand notation: ##1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5## Short hand notation: [Ar]##3d^10 4s^2 4p^5##

These are the steps which I think you should follow when writing :1. Determine the position of the element in and the total number of electrons in the atom or simple ion.

• E.g: Bromine: group 17, period 4, total number of electrons: 35

2. Start assigning electrons in increasing order of main energy levels and sublevels (using aufbau diagram below)

• Start from the bottom left (1s) and add electrons in the order shown the arrows.
• Remember:s-sublevel has 2 electrons p- sublevel has 6 electrons d- sublevel has 10 electrons f- sublevel has 14 electrons

3. Continue assigning electrons by filling each sublevel before going to the next sublevel, until all of the electrons are assigned.

• E.g: after doing 2 +3, your answer should be: ##1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5##

4. The sum of the superscripts should equal the total number of electrons. (Source: Nelson Chemistry 12)

YOU ARE DONE Have a nice day :)